#!/bin/bash

load_db()
{
    [ -e /tmp/db ] && source /tmp/db
}

save_db()
{
    for var in ${!DB_@}; do
        echo "$var=${!var}" > /tmp/db
    done
}

DB_A=0
load_db
((DB_A++))
save_db
echo $DB_A

cat /proc/sys/kernel/random/uuid
